chore(deps): update dependency lint-staged to v7

Author: renovate-bot

package.json

@@ -19,7 +19,7 @@
     "@types/webpack": "3.0.10",
     "conventional-changelog-cli": "1.3.3",
     "husky": "0.14.3",
-    "lint-staged": "4.2.1",
+    "lint-staged": "7.1.2",
     "prettier": "1.7.0",
     "typescript": "2.5.2",
     "validate-commit-message": "3.0.1"